The autonomous navigation technology for agricultural machine is profoundly studied by the developed countries, and the products are also widely applied in practice. However, the research of autonomous navigation technology in China is still backward, and the practical use is even worse. To speed up the agricultural modernization, some researches have been conducted on the electro-hydraulic servo based feedback system and the full-hydraulic steering gear driven by the stepper motor. However, the researches are mainly focused on the research achievements of universities, which is far from the being used in practice.
The automatic steering technology is one of the key technologies for intelligentizing the agricultural machine. Under severe conditions of the production environment, steering control of agricultural machine in agriculture industry is significantly different with that of the vehicle traveling on a common road. The agricultural machine works in an environment with unpredictable terrain and rugged pavement with various hardness. Thus, the steering control device of agricultural machine in agriculture industry needs to adapt different states of the vehicle and take a proper strategy according to different working conditions, such that a generally agile and accurate control is required. Therefore, development and research of the most economical and practical automatic steering control device of agricultural machine play an important role in achieving precision agriculture.